New Data Presented at ESTRO 36 Demonstrate Various Applications of the CyberKnife System

Studies show the system provides excellent outcomes throughout the cancer treatment journey, from primary cases to recurrence and metastatic disease

May 11, 2017 — Accuray Inc. announced that studies on the clinical use of the CyberKnife System continue to demonstrate its benefits across a wide range of cancer indications and stages in the cancer treatment journey. More than 50 studies were presented during poster and oral sessions at the 36th Annual European Society for Radiotherapy & Oncology (ESTRO) Meeting in Vienna, Austria, May 5 - 9, 2017. Some of the studies presented show long-term efficacy and safety with median follow-up exceeding five years.

Safety, efficacy and quality of life (QOL) outcomes were reported for 309 patients with low- or intermediate-risk prostate cancer receiving SBRT administered with the CyberKnife System. The study showed cancer control was excellent in both risk groups with 97 percent of patients free from recurrence at five years. Transient decreases in bowel and urinary QOL were observed, but returned to baseline. Twenty-one U.S. hospitals participated in this prospective study including Swedish Cancer Institute in Seattle and Beth Israel Deaconess Medical Center in Boston;

A study evaluated the long-term results of CyberKnife prostate SBRT delivered either on consecutive days or every other day. The treatment was well-tolerated with high rates of five-year biochemical relapse-free survival (BRFS). Low rates of toxicity were unaffected by the treatment schedule. The research was conducted at the Hacettepe University in Ankara, Turkey; and

Long-term results of another study conducted on 329 patients with low- and intermediate-risk prostate cancer revealed that extreme hypofractionated radiotherapy delivered with the CyberKnife System is well tolerated and safe with comparable late toxicity as other treatment modalities. Clinicians of the Erasmus MC Cancer Institute, in Rotterdam (The Netherlands) conducted the study.

Another group of studies examined the applications of the CyberKnife System for recurrent disease:

Although re-irradiation of recurrent diseases can be challenging in clinical practice, four European studies confirmed its feasibility in prostate and rectal cancer, as well as in recurrent high-grade gliomas. These studies concluded that re-irradiation with the CyberKnife System is well-tolerated and effective in controlling local recurring disease;

A study of CyberKnife SBRT for oligorecurrent liver disease showed treatment was well-tolerated and resulted in favorable survival data. Clinicians at three European hospitals conducted the research; and

A study evaluated the efficacy and toxicity of single-fraction SBRT for isolated nodal failure in prostate cancer patients, after primary surgical or radiation treatment. Treatment with the CyberKnife System provided excellent tolerability and promising biochemical control at 13 months' follow-up. Research was conducted at three Italian hospitals.

A third group of studies assessed the impact of the CyberKnife System for metastatic disease:

A study of patients with solitary extracranial metastases from gynecologic malignancies demonstrated that SBRT delivered with the CyberKnife System is well-tolerated and highly effective. An excellent five-year local control of 93.7 percent was achieved in patients with classical ovarian and uterine primary tumors. Research was conducted at Georgetown University Hospital in Washington, D.C.

Another study evaluated 206 patients with 326 inoperable pulmonary oligometastases, from colorectal tumors, lung cancers, melanoma, sarcoma, breast carcinoma and from other sites, treated with SBRT. This long-term follow-up study showed good local control (83 percent at two years and 73 percent at five years) and overall survival (Two-, three- and five-year OS rates were 63, 47 and 30 percent, respectively), as well as low rates of serious toxicity. Research was conducted at Erasmus MC-Daniel den Hoed Cancer Center in Rotterdam (The Netherlands);

New studies reinforce previous data demonstrating intracranial and extracranial treatments delivered using the CyberKnife System InCise Multileaf Collimator result in comparable target coverage and organ-at-risk sparing to the Iris Collimator, while significantly reducing treatment times (15 to 47 percent reduction compared to Iris plans depending on tumor type). Research was conducted at six European hospitals; and

The first study to use three-dimensional performance analysis of the Synchrony Respiratory Tracking System found it successfully tracks lung tumors regardless of the amplitude of movement. Research was conducted at Hacettepe University in Ankara, Turkey.

The CyberKnife System was designed to deliver treatment beams of different size and shape from hundreds of non-coplanar, isocentric or non-isocentric angles around the patient, enabling the clinician to deliver high-quality treatment plans with extreme precision, sparing surrounding healthy tissue and structures. The system's tracking capabilities eliminate the need for gating techniques and restrictive head frames, providing greater comfort for the patient.